Image of Rocky Mountain Wood Tick

Description:

This photograph depicts a dorsal view of both a female (Lt), and male (Rt) Rocky Mountain wood tick, Dermacentor andersoni. This tick specie is a known North American vector of Rickettsia rickettsii, which is the etiologic agent of Rocky Mountain spotted fever. Note the smaller size of the female’s scutum compared to the male’s larger scutum. From the Latin word for shield, the scutum, i.e., dorsal shield, covers only a small part of the female’s dorsal surface, thereby, enabling her abdomen to expand, becoming engorged during feeding. The male’s scutum covers his entire dorsal surface, and is mottled with brown markings overall, while the female’s small scutum sports an almost entirely a cream-colored gray surface.
Created: 2008